Michael Walli, Sister Megan Rice, and Greg Boertje-Obed knew they were risking prison when they staged a daring July, 2012 peace demonstration at a Tennessee nuclear facility. Now, their prospects for lengthy sentences have increased after government prosecutors added a new charge and a U.S. magistrate judge rejected a request for dismissal.

But the three activists say they are willing to sacrifice their freedom for their message. “Hopefully, one day, the need to avoid the self-destructive practice of preparing for nuclear war will be as common knowledge as not putting your hand on a hot stove,” Rice says. “If we are put in prison, it will just make the message of truth a stark one.”

After Walli, Rice, and Boertje-Obed rejected an offer to plead guilty, Assistant U.S. Attorneys for the Eastern District of Tennessee responded in early December by charging them with a more serious crime of sabotaging the Y-12 National Security Complex in Oak Ridge, Tennessee. A few weeks later, U.S. Magistrate Judge C. Clifford Shirley, Jr. denied a request that the charges be dismissed. When the trial set for May 7th occurs, Walli, Rice, and Boertje-Obed each face as much as 35 years in prison.

That trial will revisit the pre-dawn events of July 28th, when Walli, Rice, and Boertje-Obed passed through four separate fences, video surveillance, and motion detectors to reach the outside of the Highly Enriched Uranium Materials Facility. There, the group that takes its name of Transform Now Plowshares from Isaiah 2:4 (“They shall hammer their swords into plowshares and their spears into pruning hooks”) stretched crime scene tape across the area and hammered on the corner of the building. They also hung banners and spray-painted messages on the structure, including “Work for peace, not for war” and “Woe to the empire of blood.” When guards finally arrived, the activists read aloud a statement accusing the facility of being a haven for war crimes.

That accusation also formed the basis of the motion to dismiss the resulting criminal charges, but Magistrate Shirley rejected the argument. The question of war crimes is “simply irrelevant” to the request for dismissal, the judge ruled. But he also expressed his view that the creation and maintenance of nuclear weapons is not a criminal act. “When weapons are possessed to deter others, the precise intent is not to use them. The Court considers the situation to be analogous to the junkyard owner who posts a sign saying “mean dog” inside his junkyard . . .(t)he junkyard owner posts the sign to deter acts on the part of others so that the dog will not have to bite.”

Rice, a Roman Catholic nun and longtime peace activist, was dismayed by the judge’s ruling and his rationale. “It is a scientific fact that the planet can be exterminated by what is going on in this nuclear industry,” she said. “The truth is that nuclear weapons production is a war crime, and it is going on right there at the Y-12 facility, but that truth is being denied by misinformation and silence.”

One of the largest nuclear weapons production and storage facilities in the world, Y-12 holds over 400 tons of enriched uranium, enough to arm thousands of weapons. The complex also produces and stores components of nuclear weaponry and refurbishes and replaces existing warheads. Despite the judge’s statement, Y-12’s legacy goes far beyond deterrence: it produced the highly enriched uranium that fueled the nuclear bomb dropped on Hiroshima in 1945, killing tens of thousands of civilians.

The group Oak Ridge Environmental Peace Alliance has researched the activities at Y-12 and supported many activists who have trespassed on the grounds over the years to protest the facility’s work. But the extent of the breach achieved by Walli, Rice, and Boertje-Obed was unprecedented, triggering a lockdown of the facility and serious questions about the protection of the nation’s nuclear arsenal. The Bulletin of the Atomic Scientists reported on the incident with the headline, “Security at Y-12 Nun Too Good.”

The ultimate security risk at Y-12 is to global civilization, the activists insist. University of Illinois law professor Francis X. Boyle told the court that Y-12 is indeed the site of ongoing war crimes and that the demonstration on July 28th was well-justified. The activists’ legal team argued to the court, “If these people took this action in Iran, the U.S. government would praise them. But, in Tennessee, the U.S. government prosecutes them.”

Walli, Rice, and Boertje-Obed are certainly not receiving the government’s praise, but others have been energized by their example. “A robust movement can begin with a single, courageous action like the one at Oak Ridge,” wrote Nathan Schneider, editor of the news site Waging Nonviolence. Not only did the three gray-haired activists risk their lives to make their statement—deadly force is authorized to protect Y-12’s grounds—but they may be facing the equivalent of a life sentence for their protest. “These wonderful people are risking jail, maybe for the rest of their lives, in order to tell the truth about the potential for global peril,” says William Quigley, a Loyola University law professor and member of the three activists’ legal team. (Full disclosure: Quigley is my brother.)

Since Rice is 82 years old, she appears to be at greatest risk for a de facto life sentence. (Walli is 63, Boertje-Obed is 57.) It is a possibility she is at peace with. Rice traces her concerns about nuclear war back to the harrowing stories of suffering told by her uncle, a U.S. Marine stationed in Nagasaki after the U.S. bombing in 1945. When Rice returned to the U.S. after spending most of four decades teaching school in Nigeria and Ghana, she received the permission of her order, the Society of the Holy Child Jesus, to devote herself to peace activism. She has since been arrested dozens of times for civil disobedience and served a six-month term in federal prison for an action on the grounds of the former School of Americas in Fort Benning, Georgia.

Rice hopes that she and Walli and Boertje-Obed will be able to convince a Tennessee jury that the true criminal act at Y-12 is the production of weapons of mass destruction, not a symbolic gesture by three activists armed with flashlights and bolt cutters. There is some hopeful precedent. In 2006, an Irish jury acquitted four peace activists who used hammers to inflict damage on a U.S. military plane en route to the war in Iraq. In 2010, a magistrate in Australia delivered a not guilty verdict to activists who trespassed onto an air base. Other peace demonstrators have persuaded juries that their civil disobedience was justified by their message.

But Rice realizes that kind of outcome is far from guaranteed, and she appreciates the consequences of a lengthy sentence. Rice was close friends with Sister Jackie Hudson, who fell fatally ill in 2011 while serving a prison term for anti-war civil disobedience. Among the items Rice, Walli, and Boertje-Obed carried onto the Y-12 base were white roses, a commemoration of The White Rose nonviolent resistance to Adolph Hitler in Nazi Germany. The leaders of the White Rose movement were executed.

“I feel blessed to be able to devote my life to exposing the criminality of nuclear weaponry,” Rice says. Soon, a Tennessee jury and judge will decide whether the rest of that life will be spent behind bars.

Fran Quigley is clinical professor and director of the Health and Human Rights Clinic at Indiana University McKinney School of Law.

Fran Quigley is a professor at Indiana University McKinney School of Law, where he directs the Health and Human Rights Clinic. He is the author of How Human Rights Can Build Haiti (Vanderbilt University Press).